Electrical connectors used in an underwater environment, and in particular in seismic exploration on an ocean floor, are subjected to high pressure which may cause leakage around the electrical contacts and subsequent failure of the electrical connection. Leakage of the connector assembly is a serious problem when face sealing of the connector members is relied upon to provide sealing of the mating contacts. U.S. Pat. No. 5,120,268, issued Jun. 9, 1992 to Al Gerrans discloses an underwater electrical connector having a relatively soft core in which electrical contact members are mounted. The soft core extends around the female contact member in the connector and, upon assembly of mating halves of the connector, is in intimate contact with a bore also formed in the relatively soft material of the core. It has been found that the sealing provided between two soft surfaces is less desirable than sealing a soft surface against a relatively hard surface.
The improved sealing action provided between relative hard and soft surfaces is disclosed in U.S. Pat. No. 5,387,119, issued Feb. 7, 1995 to Richard G. Wood, the inventor of the present invention. The later patent discloses an open-face waterproof electrical connector that provides sealing between a hard sheath surrounding an electrical contact and a relatively soft bore having a plurality of internally formed annular ridges, or O-ring type seals. One member of the connector is formed of single, relatively hard material that extends over the electrical contacts to form the hard sheath. The mating connector is formed of a single, relatively soft material in which the ridged bores were formed. The advantages of sealing a soft material against a hard surface as discussed in the above patent, as opposed to sealing between two soft surfaces, include decreased deformation and compression set. This arrangement described in U.S. Pat. No. 5,387,119 provides an excellent open-face waterproof connector when assembled, even underwater, but requires that each matable half of the connector assembly be separately formed of different materials. The term "open-face waterproof" means that the sealing of the electrically conductive components, against the entrance of water under pressure, is not dependent on a seal provided by a housing around the connector nor by contact between the respective faces of the mating members of an electrical connector assembly.
The present invention is directed to overcoming the problems set forth above. It is highly desirable to have an underwater electrical connector assembly having mating components that are open-face waterproof and can be constructed and arranged to provide a variety of male-female contact combinations. It is also desirable to have an underwater connector assembly in which both mating components may be formed with preformed cores of the same material that provides a hard sheath around selected contacts, and relatively soft, compressible molded housings that encapsulate the cores and provide a ridged bore that seals against and around each of the sheaths of a mating connector.